1. Field of the Invention
The present invention relates to a data communication apparatus, a method and a system therefor, and a program for data communication process stored in a memory medium, and more particularly to a technology for causing plural devices corresponding to communication methods of different formats to be recognized as a single communication system.
2. Related Background Art
Recently there is actively investigated, in constructing a communication system with electronic device such as a personal computer, a printer, a hard disk, a digital camera, a digital video camera etc., the connection of such device through digital interfaces corresponding to a communication method of a common format, thereby realizing high-speed data communication.
Among the next-generation high speed digital interfaces developed from such standpoint, there is known a digital interface based on the IEEE 1394-1995 high performance serial bus standard (hereinafter called IEEE 1394 standard). The IEEE 1394 standard defines two transfer methods, namely the isochronous transfer mode and the asynchronous transfer mode. The isochronous transfer mode ensures the transmission and reception of a predetermined amount of data in each communication cycle (125 xcexcs) and is executive for the real-time transfer of image signal or voice signal, while the asynchronous transfer mode executes transmission and reception asynchronously with the communication cycle and is executive for transmitting and receiving the control commands and the file data whenever necessary. In each communication cycle time, the asynchronous mode has a lower priority in comparison with the isochronous mode.
Also in the IEEE 1394 standard, the configuration of connection of the communication system can be automatically recognized. More specifically, in response to a change in the configuration of connection, resulting from the addition of a new device, the deletion of a connected device, the on/off operation of power supply of a connected device, there is automatically executed the recognition of the configuration of connection of the newly constructed system and the setting of ID information for the device constituting such system.
Furthermore, the IEEE 1394 standard is provided with a function of relaying the data transmitted from each device. Thus the communication packet, transmitted from each device in the isochronous transfer mode or the asynchronous transfer mode, is transferred, by such relaying function, to all the device on the communication system.
The details of the IEEE 1394 standard are described in the xe2x80x9cIEEE Standard for a High Performance Serial Busxe2x80x9d published by Institute of Electrical and Electronics, Inc. on Aug. 30, 1996.
FIG. 1 illustrates an example of a serial-bus type communication system constituted by plural electronic device equipped with the digital interfaces based on the IEEE 1394 standard (hereinafter written as 1394 interface). In the example shown in FIG. 1, the electronic device are connected in a tree shape configuration.
In FIG. 1, there are shown a personal computer 103, a portable digital VTR 102 such as a digital camcorder, a desk-top VTR 103 capable, for example, of dubbing the digital image data of the camcorder 102, and communication cables 104 connecting the 1394 interfaces provided on the electronic device.
In case of connecting a portable device such as the digital camcorder 102 to such communication system, it has been necessary to make the connection with the communication cable 104 as shown in FIG. 1. However the connection of the portable device with the communication cable has been associated with drawbacks that the connecting operation is cumbersome and that the freedom of connection is lost, depending on the length and the shape of such communication cable. In particular, in the portable device in which the compactness is an essential factor, there is encountered a difficulty of providing the connector for the communication cable in a limited space.
In consideration of such inconvenience of connection with the communication cable, it is conceivable to connect the portable device by a wireless system to the above-mentioned communication system, by a wireless communication method based for example on the IrDA (Infrared Data Association) standard. In such case, however, such portable device, executing communication according to the communication method of a standard different from the IEEE 1394 standard, can communicate with the device capable of accommodating such communication method but is incapable of communicating with the entire communication system mentioned above. Also the communication system capable, as explained above, of automatically recognizing the connection of a new device cannot recognize such portable device which utilizes the communication method different from the IEEE 1394 standard. Therefore, in order to execute communication between such portable device and the device constituting the above-mentioned communication system, each device has to be provided with a communication interface corresponding to the communication method same as that employed in the portable device.
An object of the present invention is to solve the above-described drawbacks.
Another object of the present invention is, in a data communication apparatus, to cause a device corresponding to the communication method of a standard different for example from the IEEE 1394 standard on which the communication system is based, to be recognized as a component of such communication system. Also it is to cause a function of the device corresponding to the communication method of a standard different from that of the communication system to be recognized as a function provided in the device constituting such communication system.
As a preferred embodiment of the present invention for such objects, there is disclosed a data communication apparatus comprising:
a) first communication means for executing communication based on a first communication method;
b) second communication means for executing communication based on a second communication method different from the first communication method; and
c) setting means for setting ID information for identifying a device executing communication based on the first communication method, on a device executing communication with the second communication means.
As another preferred embodiment of the present invention for such objects, there is disclosed a data communication apparatus connectable to a communication system including plural devices corresponding to a common communication method, comprising:
a) a communication interface corresponding to a predetermined communication method, which is different from the common communication method; and
b) means for causing each of the devices of the communication system to recognize a device capable of communication with the communication interface as one of the devices of the communication system.
As still another preferred embodiment of the present invention for such objects, there is disclosed a data communication apparatus comprising:
a) first communication means corresponding to a first communication method;
b) second communication means corresponding to a second communication method different from the first communication method; and
c) setting means for resetting information to be used by the first communication means, relating to the data communication apparatus according to a connection status of the second communication means.
As still another preferred embodiment of the present invention for such objects, there is disclosed a data communication apparatus connectable to a communication system including plural devices corresponding to a common communication method, comprising:
a) a communication interface corresponding to a predetermined communication method, which is different from the common communication method; and
b) means for causing each of the device constituting the communication system to recognize a function of a device capable of communication with the communication interface as a function of the data communication apparatus.
Still another object of the present invention is, in a data communication method, to cause a device corresponding to the communication method of a standard different for example from the IEEE 1394 standard on which a communication system is based, to be recognized as a component of such communication system. Also it is to cause a function of the device corresponding to the communication method of a standard different from that of the communication system to be recognized as a function provided in the device constituting such communication system.
As a preferred embodiment of the present invention for such object, there is disclosed a data communication method adaptable in an apparatus executing communication based on a first communication method and communication based on a second communication method different from the first communication method, comprising a step of:
setting ID information for identifying a device executing communication based on the first communication method, on a device executing communication based on the second communication method.
As another preferred embodiment of the present invention for such object, there is disclosed a data communication method adaptable in an apparatus provided with a first communication interface corresponding to a first communication method and a second communication interface corresponding to a second communication method different from the first communication method, comprising a step of:
resetting information to be used by the first communication interface, relating to the apparatus and according to the connection status of the second communication interface.
As still another preferred embodiment of the present invention for such object, there is disclosed a data communication method adaptable in a communication system including plural devices corresponding to a common communication method, comprising steps of:
a) executing communication with a predetermined device, based on a communication method different from the common communication method; and
b) causing each of the device of the communication system to recognize the predetermined device as one of the device of the communication system.
As still another preferred embodiment of the present invention for such object, there is disclosed a data communication method adaptable in a communication system including plural devices corresponding to a common communication method, comprising steps of:
a) executing communication with a predetermined device, based on a communication method different from the common communication method; and
b) causing each of the device constituting the communication system to recognize a function of the predetermined device as a function of the device executing communication based on the different communication method.
Still another object of the present invention is, in a data communication system, to cause a device corresponding to the communication method of a standard different for example from the IEEE 1394 standard on which a communication system is based, to be recognized as a component of such communication system. Also it is to cause a function of the device corresponding to the communication method of a standard different from that of the communication system to be recognized as a function provided in the device constituting such communication system.
As a preferred embodiment of the present invention for such object, there is disclosed a data communication system comprising:
a) a first communication apparatus corresponding to a first communication method; and
b) a second communication apparatus corresponding to a second communication method different from the first communication method;
wherein ID information for identifying a device executing communication based on the first communication method is set for the second communication apparatus.
As another preferred embodiment of the present invention for such object, there is disclosed a data communication system comprising:
a) a first communication apparatus corresponding to a first communication method; and
b) a second communication apparatus corresponding to a second communication method different from the first communication method;
wherein information relating to the first data communication apparatus is reset according to a connection status of the first communication apparatus and the second communication means.
As still another preferred embodiment of the present invention for such object, there is disclosed a data communication system includes plural devices corresponding to a common communication method, comprising:
a) a communication apparatus corresponding to a predetermined communication method, which is different from the common communication method; and
b) a device for causing each of the communication apparatus constituting the communication system to recognize the communication apparatus as one of the communication apparatus constituting the communication system.
As still another preferred embodiment of the present invention for such object, there is disclosed a data communication system includes plural devices corresponding to a common communication method, comprising:
a) a communication apparatus corresponding to a predetermined communication method, which is different from the common communication method; and
b) a device for causing each of the device constituting the communication system to recognize a function provided in the communication apparatus as a function of the device capable of communication with the communication apparatus.
As still another preferred embodiment of the present invention for such object, there is disclosed a data communication system, comprising:
a) a first apparatus for setting plural ID information, to be utilized communication based on a predetermined communication method; and
b) a second device executing communication with a device corresponding to a communication method different from the predetermined communication method, utilizing predetermined ID information.
Still another object of the present invention is, in a program for a data communication process contained in a computer readable medium, to cause a device corresponding to the communication method of a standard different for example from the IEEE 1394 standard on which a communication system is based, to be recognized as a component of such communication system. Also it is to cause a function of the device corresponding to the communication method of a standard different from that of the communication system to be recognized as a function provided in the device constituting such communication system.
As a preferred embodiment of the present invention for such object, there is disclosed a program for a data communication process adaptable in an apparatus including a first communication interface corresponding to a first communication method and a second communication interface corresponding to a second communication method different from the first communication method, the program being contained in a medium readable by a computer, comprising a step of:
resetting information relating to the apparatus and adapted to be used by the first communication interface, according to a connection status of the second communication interface.
As another preferred embodiment of the present invention for such object, there is disclosed a program for a data communication process adaptable in a communication system including plural devices corresponding to a common communication method, the program being contained in a medium readable by a computer, comprising steps of:
a) executing communication with a predetermined device based on a communication method different from the common communication method; and
b) causing each of the device of the communication system to recognize the predetermined device as one of the device of the communication system.
As still another preferred embodiment of the present invention for such object, there is disclosed a program for a data communication process adaptable in a communication system including plural devices corresponding to a common communication method, the program being contained in a medium readable by a computer, comprising steps of:
a) executing communication with a predetermined device based on a communication method different from the common communication method; and
b) causing each of the device constituting the communication system to recognize a function of the predetermined device as a function of the device executing communication based on the different communication method.
Still other objects of the present invention, and the advantages thereof, will become fully apparent from the following detailed description of the embodiments.